That is expected to be supplied by Andy Pettitte, but general manager Brian Cashman can’t predict an exact date when the 40-year-old lefty will come off the disabled list. Pettitte has been out since June 27 with a fractured left ankle.

“We have to let the healing process take its course,’’ said Cashman, who expects to see Pettitte pitching next month in the big leagues. “He had that setback which cost him a week to 10 days, but he is in the middle of the healing process.’’

Pettitte, who is 3-3 with a 3.22 ERA in nine starts, said on July 29 that an X-ray two days before didn’t show the amount of healing expected.

“Obviously, it’s healing up but it hasn’t healed up as much as [Dr. Chris Ahmad] thought,’’ Pettitte said referring to the Yankees’ physician.

Pettitte threw off flat ground in Oakland (July 19-22) and admitted he pushed it too far in Seattle later on the trip.

“In Seattle it swelled up,’’ Pettitte said. “I did a little too much in Seattle. Now I am laying low. I have to take it easy.’’

Pitching coach Larry Rothschild said he doesn’t know when Pettitte will be able to throw off a mound and is waiting to find out how much the time off will affect Pettitte.

“We have tried to keep his arm in shape, but I won’t know until he gets through it, how it will impact him until he faces hitters,’’ Rothschild said Thursday. “It’s hard to tell but as long as the bone is healed he should be OK.’’

Pettitte, whose season didn’t begin until May 13 after he came out of retirement, is 3-3 with a 3.22 ERA in nine starts.

Nova has worked 10 ¹/₃ innings in the past two starts and given up 16 earned runs and 21 hits. Garcia has failed to go six innings in four of his previous seven outings.

***

With the Blue Jays starting three lefties in a three-game series in Toronto beginning Friday night, Andruw Jones will get dusted off and put in the lineup in left field or as the designated hitter.

Jones’ last start was on Aug. 1 against Baltimore lefty Zach Britton at Yankee Stadium and he went 1-for-3 with a sacrifice fly and got hit by a pitch. Since then Jones has one at-bat on Aug. 5 as a pinch-hitter against Mariners lefty Lucas Luetge.

Jones is hitting .225 (25-for-111) with eight homers and 18 RBIs against lefties and .222 (12-for-54) with four homers and 10 RBIs versus righties.

Manager Joe Girardi wasn’t specific where Jones would play but predicted a heavy workload.

“Jones will get a lot [of playing time],’’ said Girardi, who might want to keep Raul Ibanez off the Rogers Centre artificial turf and give Ichiro Suzuki a rest.

Girardi also didn’t sound like a manager who will play Eric Chavez, who went 2-for-4 with a homer and an RBI in Thursday’s 4-3 come-from-behind victory, three straight games on the turf.

“I don’t know, we will have to take a look at it,’’ Girardi said. “It’s three days on turf.’’

Chavez, who went 2-for-4 with a homer and an RBI yesterday, is batting .467 (14-for-30) with four homers and nine RBIs in the last nine games, understands he might not play at all in Toronto.

“I am not an every-day guy, I have to accept that,’’ Chavez said.

The Yankees are 22-14 against lefty starters this year. The .611 winning percentage is tied for the top AL spot with the Red Sox.

***

Nick Swisher was the DH and went 0-for-5 and whiffed twice. It was Swisher’s 10th start as the DH. According to Girardi, it was nothing more than a move designed to keep Swisher fresh.

“We are trying to rotate [the DH]. It’s a day game after a night game and we are playing 20 in a row,’’ Girardi said. “Make sure we keep them healthy.’’

***

Tim Welke’s controversial call on Andy Dirks’ fly ball to left in the fifth inning wasn’t the only one that ticked off the Yankees.

Mark Teixeira said first base umpire Tony Randazzo blew a call in the seventh on Omar Infante’s ground ball to short.

“I didn’t want to get thrown out,’’ said Teixeira, who didn’t argue. “But he was out.’’